Couldn't connect to Docker daemon on ubuntu

I am using docker-compose-version 1.7.0,
Not using docker machine:
$ docker-machine ls
NAME ACTIVE DRIVER STATE URL SWARM DOCKER ERRORS

it all worked perfectly for weeks…
Now when i try running
docker-compose up
i get this error:
Couldn't connect to Docker daemon-you might need to run docker-machine start default.
I cant figure out what happened, any ideas?

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  • One Solution collect form web for “Couldn't connect to Docker daemon on ubuntu”

    Run it with sudo.
    Its bad to run docker with sudo so you should add your user to the docker group
    https://askubuntu.com/questions/477551/how-can-i-use-docker-without-sudo

    Docker will be the best open platform for developers and sysadmins to build, ship, and run distributed applications.